The use of harness reels is known in the background art. For instance, U.S. Pat. No. 4,801,105 to Frisk discloses a reel assembly for retracting and locking a shoulder harness. The assembly includes a strap supporting spool affixed to a ratchet wheel. When a strap is rapidly pulled from the reel, an inertia mass turns with respect to the reel. This causes the inertia mass to move forward axially and trip a dog which locks the reel.
Likewise, U.S. Pat. No. 5,636,807 to Warrick discloses an acceleration sensor for an aircraft employing an inertia weight. The inertia weight is movable within a chamber by way of a linkage. The linkage is such that it provides the same output in response to movement of the aircraft in multiple directions.
Although these inventions each achieve their respective objectives, there continues to be a need in the art for a reel assembly with a means to easily and effectively limit the maximum payout of the tether from the reel.
An aircrew restraint system is disclosed in commonly owned U.S. Pat. No. 7,275,710 to VanDruff et. at. VanDruff discloses a mobile aircrew restraint system that includes an overhead track and a trolley that runs along the track. The trolley carries a retractor which releases a webbing strap attached to a harness. The strap retractor is attached to the trolley and is controllable to limit the payout of the webbing strap.
Although each of the foregoing examples achieves its own particular objective, all suffer from common drawbacks. For example, none of these systems permit the payout of tether from a reel to be adjusted.